JPH01205206A - Industrial robot - Google Patents

Abstract

PURPOSE:To improve a work efficiency at the time of teaching and at the time of reproducing by providing an arithmetic means to correct the data for the robot for work based on the position feedback data of the industrial robot reproduced by the data for the robot for the work. CONSTITUTION:Since an arithmetic means 22 to correct the data for robots 5 and 8 for work based on the position feedback data of robots 5 and 8 for work reproduced by the data for the robots 5 and 8 for the work is provided, the command value, in which the same orbit as a target orbit formed by a robot 1 for teaching can be executed by the robots 5 and 8 for the work, can be formed automatically and with a good accuracy. Consequently, teaching data can be prepared without providing any limit for the action speed and action environment of the robot 1 for teaching, and it is not necessary to stop once the line for the robots 5 and 8 for the work and correct and change the data at the time of reproduction. Thus, the efficiency at the time of teaching and at the time of the work can be improved.

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention relates to an industrial robot having a teaching robot and a working robot located on a production line, and particularly relates to an industrial robot having a teaching robot and a working robot located on a production line. This invention relates to an industrial robot suitable for use in cases where the dynamic characteristics of the robot and the robot do not necessarily match.

"Conventional technology" Conventionally, teaching data is created using a working robot located on a production line and a teaching robot in an offline state or a model robot in an offline teaching system.
When making the working robot perform work based on this teaching data, a P/Dram conversion device is connected to the teaching pot and the working k-t to transfer the teaching data to the working robot. A suitable conversion may be performed.

This program conversion device corrects the instrumental error between the teaching robot or model robot and the working robot, and corrects the relative positional relationship between the robot and the workpiece (worked object). In this case, the program conversion device converts the teaching data so that the static trajectory of the teaching robot during teaching matches the static trajectory of the working robot during playback.

``Problems to be Solved by the Invention'' However, in the conventional program conversion device, data conversion was performed to match the static trajectories of the teaching robot and the working robot, respectively.
No consideration was given to the differences in dynamic characteristics between these teaching robots and working robots. Therefore, when the teaching robot and the working robot have different dynamic characteristics, a phenomenon occurs in which the reproduction trajectory deviates from the teaching trajectory as the operating speed increases. For this reason, restrictions have been placed on the operating speed and operating environment of the teaching robot during teaching, but such restrictions make it difficult to improve work efficiency during teaching or playback. I was in a situation. In addition, during work, it becomes necessary for workers to monitor the actual trajectory of the robot on the line, and if the trajectory during playback actually deviates from the trajectory during teaching, the production line must be stopped temporarily. The production line had to be stopped for a long time in order to modify or change the data of the work robot, which was extremely inefficient.

On the other hand, in order to avoid this phenomenon, if the dynamic characteristics of the teaching robot are made to match those of the working robot, when there are multiple working robots with different dynamic characteristics on the production line, these dynamic characteristics It was necessary to create multiple sets of different data for different working robots, which was also very inefficient.

This invention was made in view of the above-mentioned circumstances, and it is possible to create teaching data without considering the dynamic characteristics and environment of the working robot at the time of teaching, and to create data at the time of playback based on the trajectory at the time of teaching. The aim is to create an industrial robot that can accurately reproduce trajectories.

"Means for Solving the Problem" Therefore, in the present invention, a teaching robot, a working robot located on a production line, a robot connected to the teaching robot and the working robot, and a position of the teaching robot are provided. In an industrial robot having a program converting device for converting feedback data into data for a working robot, the program converting device is configured to transmit position feedback data of the working robot reproduced from the data for the working robot. The above-mentioned problem is solved by providing a calculation means for correcting the data for the working robot.

"Embodiments" Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 and 2 are diagrams showing an embodiment in which the industrial robot of the present invention is applied to a coating system for coating a workpiece (object to be worked) as shown in FIG. First, the overall configuration of the industrial robot of this embodiment will be explained with reference to FIG. 1. This industrial robot is a mother robot (teaching robot) that is provided for teaching and has an m-th degree of freedom. 1, a teaching device 3 connected to this mother robot 1 to control the mother robot 1, and first and second painting robots ( work robot)
5.8, a working device 6.9 that is connected to the painting robot 5.8 and controls them, and a communication means (not shown in FIG. 1) for the teaching device 3 and the working device 6.9, respectively. A program that exchanges data between the teaching device 3 and the working device 6.9 and converts the teaching data obtained from the teaching device 3 according to the painting robot 5.8. It is composed of a converting device 4. In this embodiment, a so-called laptop-type personal computer with excellent portability is used as the program conversion device 4, and is composed of a display section 4a and a main body of the arithmetic processing section 4b. Furthermore, the workpieces 7 and 10 to be worked on by the first and second painting robots 5 and 8 are the same as the workpiece 2 used for teaching by the mother robot l.
Or workpieces of similar shape are used.

Next, the configuration of each part will be explained with reference to FIG. 2.

In the teaching device 3, a teaching data storage means 11, an interpolation calculation means 12, and a robot drive signal output means 13 are connected in series, and the output of the robot drive signal output means 13 is supplied to the mother robot 1. The position feedback data from the mother robot I is sampled by the sampling means 14 and then input to the position feedback data storage means 15. The output of this position feedback data storage means 15 is supplied to communication means 16.

Further, in the arithmetic processing section 4b, a communication means 17, a taught data storage means 19, and a taught data converting means 20 are connected in series, and the output from the taught data converting means 20 is inputted to a changeover switch 21. The C terminal of the changeover switch 2 is connected to the second virtual target trajectory data storage means 25, while the B terminal is input to the learning control calculation means 22. The output of the second trajectory data storage means 25 is inputted to the first virtual target trajectory data storage means 24 and the auxiliary storage means 26, and the first target data storage means 24 is connected to the learning control calculation means 22, Second storage means 25
The auxiliary storage means 26 is connected to the C terminal and the d terminal of the changeover switch 27, respectively. This changeover switch 27 is connected to a communication means 18, and this communication means 18 has a position feedback data storage means 23.
is connected to this position feedback data storage means 2.
3 is also connected to the learning control calculation means 22.

Further, the configurations of the working devices 6 and 9 are the same, and to explain the working device 6 connected to the first painting robot 5 as an example, in this working device 6, the output from the communication means 28 is serially connected to the first painting robot 5. The teaching data storage means 29, the interpolation calculation means 30, and the robot drive signal output means 31 are input to the storage means 29 side, and the output of the robot drive signal output means 31 is supplied to the first painting robot 5. ing. On the other hand, the position feedback data from the first painting robot 5 is sampled by the sampling means 32 and then input to the position feedback data storage means 33. Furthermore, this position feedback data storage means 33 is also connected to the communication means 28.

The communication means 16 and the arithmetic processing unit 4 of the teaching device 3
b communication means 17 and arithmetic processing unit 4b communication means 18
and the communication means 28 of the working device 6 (or the working device 9) are connected via communication cables, etc., so that the teaching device 3 and the calculation processing section 4b, and the calculation processing section 4b and the working device 6 .9, mutual communication is possible.

Next, the operation of the industrial robot having the above configuration will be explained with reference to FIGS. 1 to 3.

First, teaching data such that the mother robot 1 paints the workpiece 2 is created by direct teaching or offline teaching. This teaching data is position data θ of each degree of freedom for each posture of the mother robot 1. , (i=1 to m: degree of freedom) and the operation time ΔT of the mother robot 1 from one posture to the next posture, and is a discrete value. This teaching data is stored in the teaching data storage means ll in the teaching device 3.

Next, when transmitting teaching data from the mother robot 1, the teaching data is sequentially read out from the teaching data storage means 11, and is interpolated by the interpolation calculation means 12 to obtain continuous values that allow the mother robot 1 to operate. Convert to The converted data is supplied to the mother robot 1 via the robot drive signal output means 13, and the mother robot 1 operates based on this data. The position feedback data of the mother robot 1 at this time is the sampling means 1
4, the data is sampled into discrete values at fixed time intervals ΔT, and stored in the position feedback data storage means 15. Here, in this embodiment, the sampling interval ΔT of the sampling means 14 is
is set to a value similar to the dynamic time delay of
The position feedback data sampled by the sampling means 14 represents the continuous movement of the mother robot l. When the position feedback data is stored in the position feedback data storage means 15, this data is transferred to the arithmetic processing section 4b of the program conversion device 4 via the communication means 16, 17.

The position feedback data of the mother robot 1 transferred from the teaching device 3 is stored in the teaching data storage means 19 in the arithmetic processing section 4b of the program converting device 4 via the communication means 17 (step 3 in FIG. 5P2).

Next, the position feedback data of the mother robot 1 stored in this storage means 19 is stored in the painting robot 5.
8 when performing painting work, and the teaching data conversion device 20 provides information to these painting robots 5.8 based on the specifications and work environment data of the painting robots 5.8 stored in advance. Directly applicable teaching data θ+(i+j)(+-1=m: degree of freedom, j=o~
! , : number of taught data) (step 5P3 in FIG. 3). As described above, if the operation time is sufficiently slow, this teaching data θ1 (11j) can cause the painting robot 5.8 to perform the same operation as the mother robot 1.

When teaching data is first output from the teaching data conversion device 20 (if the judgment in step 5P2 in FIG. The target trajectory data is stored in the target trajectory data storage means 25 (step 5P7 in FIG. 3). The teaching data stored in the trajectory data storage means 25 at this time is θe (++j) (i = l"m: degree of freedom, j-0 ~
1. : Number of teaching data). In this state, θ1(11
3) −θ8(I, j).

Teaching data θ stored in the second trajectory data storage means 25
B(IIJ) is the first virtual target trajectory data storage means 24
and is transferred to the auxiliary storage means 26.

In this embodiment, a disk drive having a floppy disk, a hard disk, etc. as a storage medium is used as the auxiliary storage means 26, and even if the teaching data θB(i, j) is transferred multiple times, the transfer order is memorized. Moreover, the structure is such that it can be read out separately at the time of reading. On the other hand, when the teaching data θm(11j) is transferred multiple times, the first trajectory data storage means 24 cannot store the data transferred in the past, and stores only the latest data θA( i, j) (-θ+i(i, j) (step 5P9 in FIG. 3).
The teaching data stored in the trajectory data storage means 25 is transmitted to the work device 6 (or work device 9) via the communication means 1B, '28 by connecting the changeover switch 27 to the C terminal.
) (step 5P8 in FIG. 3). In addition,
The data transfer between the working device 6.9 and the arithmetic processing unit 4b and the arithmetic processing for the operation of the painting robot 5.8, which will be described later, are performed separately.

The teaching data θB(I
TJ) is stored via the communication means 28 in the teaching data storage means 29 in the working device 6.9.

Next, the teaching data stored in the storage means 29 is sequentially read out, and is interpolated by the interpolation calculation means 30 to be converted into continuous values that allow the mother robot 1 to operate. The converted data is supplied to the painting robot 5.8 via the robot drive signal output means 31, and the painting robot 5.8 operates based on this data.

At this time, the position feedback data of the painting robot 5.8 is sampled by the sampling means 32 into discrete values at the same time interval ΔT as the sampling means 14 in the teaching device 3, and the position feedback data storage means 33.

The position feedback data of the painting robot 5.8 stored in the position feedback data storage means 33 is expressed as θ(11J X+ −i−m: degree of freedom, j−o~!
, : number of teaching data).

Then, when the position feedback data θ(i, j) is stored in the position feedback data storage means 33, this data is transferred to the arithmetic processing unit 4b of the program conversion device 4 via the communication means 28.18, and is subjected to arithmetic processing. It is stored in the position feedback data 23 in the section 4b (step 5P5 in FIG. 3). Accordingly, by connecting the changeover switch 21 to the b terminal, the teaching data θ1 (ITJ) in the teaching data converting means 20 is input to the learning control calculation means 22, while the position feedback data storage means 2
Position feedback data θ(+,j) is inputted from 3, and teaching data θA(1+j) is further inputted from the first trajectory data storage means 24.

The learning control calculation means 22 performs a learning control calculation as shown in the following formula (step 5P6 in FIG. 3).

θ1l (i, j) = θA (i, j) ten Σ”K (i, k)
・(θ+(t j 3 +k)−〇(i, j+k))
However, i=1~m: degree of freedom, j−o~1. : Number of teaching data. Correction coefficient K (i, k) (k = O~,
) is a constant determined for each painting robot 5.8, and is stored in advance in the learning control calculation means 22.

The teaching data θB(IIJ) which is the result of this calculation is stored in the second virtual target trajectory data storage means 25, and is further stored in the first virtual target trajectory data storage means 24 and the auxiliary storage means 26.

Thereafter, the operation of the painting robot 5.8 is performed based on the teaching data θIt(IIJ) which is the result of this calculation, and the teaching data θs(t) is performed based on the position feedback data from the painting robot 5.8.

j) is performed by the learning control calculation means 22, and the painting robot 5.8 is operated a predetermined number of times, or θ+(i, j)−θ(i, j) is predetermined. or θII(
i, j) [n-1st time] - θII (IIj) [nth time] repeats the above operation until it becomes smaller than predetermined minute values Δθ, ε. Then, the teaching data at this time is determined as a command value to the painting robot 5.8, and the painting robot 5.8 is operated based on this.

Here, the position feedback data θ(+.

j) does not oscillate and approaches θ1(i, j), or when it oscillates and diverges without approaching θI(IIJ), do not use the above formula and calculate An evaluation function as shown in the following equation is calculated from the data of each axis of the painting robot 5.8.

Then, the teaching data θB(i, j) when the evaluation function E takes the smallest value may be selected as the command value. The selection of this command value is based on the evaluation function E for each operation.
The value may be displayed on the display section 4a of the program conversion device 4, and the operator may select the appropriate value.

Note that the details of the industrial robot of the present invention are not limited to the embodiments described above, and various modifications are possible. - As an example, in the above embodiment, a so-called laptop type personal computer with excellent portability is used as the program conversion device 4, so the installation location of the teaching system including the mother robot 1 and the teaching device 3 and the installation location of the production line are different. If the mother robot is far away, the position feedback data from the mother robot l is temporarily stored in the teaching data storage means 19 in the calculation control unit 4b.
After storing the communication means 16 and 17 in an offline state, the communication means 16 and 17 may be disconnected, and the program conversion device 4 may be moved to the production line, and then the communication means 18 and 28 may be connected. Furthermore, it goes without saying that the communication means 16, 17, and 18 may be connected through a telephone line. Furthermore, instead of the communication means 16, the teaching device 3 may be provided with auxiliary storage means such as a floppy disk drive, and data may be exchanged without going through the communication means.

Further, the number of the painting robots 5.8 is not limited to two, and even if a larger number of robots exist, it is possible to control them separately. Furthermore, the arithmetic processing section 4b of the program conversion device 4 may be provided separately on the teaching device 3 side and the working device 6.9 side. In this case, the arithmetic processing section 4b provided on the teaching device 3 side does not require a learning control arithmetic function.

Furthermore, without providing a special mother robot 1, one of the painting robots on the production line may be used as a mother robot, and without providing a mother robot 1, an offline teaching model may be used. The position feedback data may be obtained from the operation of the controller. As a matter of course, the scope of application of the industrial robot of the present invention is not limited to painting work, but can be applied as a robot for performing various types of work.

"Effects of the Invention" As explained in detail above, according to the present invention, the operation for correcting the data for the work robot based on the position feedback data of the work robot reproduced by the data for the work robot. Since the means is provided, it is possible to automatically and accurately create a command value that allows the working robot to execute the same trajectory as the target trajectory created by the teaching robot. As a result, it is possible to create teaching data without placing any restrictions on the operating speed or operating environment of the teaching robot, and at the same time, during playback, the line can be temporarily stopped for the working robot to modify the data. Since there is no need to make any changes, efficiency during teaching and work can be greatly improved.

Moreover, since there is no need for workers to check the actual trajectory of the work robot on the line, worker safety can also be ensured. Furthermore, since the teaching data is modified based on the position feedback data of each work robot, it is possible to teach work robots with different dynamic characteristics at the same time based on the same teaching data. Efficiency is greatly improved.

[Brief explanation of the drawing]

1 and 2 are diagrams showing an industrial robot that is an embodiment of the present invention, in which FIG. 1 is a block diagram showing the entire robot, and FIG. 2 is a teaching device, a program conversion device, and a working device. FIG. 3 is a flowchart for explaining the operation of an industrial robot according to an embodiment of the present invention. l...Mother robot (teaching robot), 4
・・・・・・Program conversion device, 5.8・・・・・・
Painting robot (work robot), 22...
Learning control calculation means (calculation means).

Claims (1)

[Claims] a teaching robot, a working robot located on a production line, and a program conversion device that is connected to the teaching robot and the working robot and converts position feedback data of the teaching robot into data for the working robot. an industrial robot, the program converting device including arithmetic means for correcting the data for the working robot based on position feedback data of the working robot reproduced from the data for the working robot; An industrial robot characterized by being provided with.